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Securities - Investments in Pooled Trust Preferred Securities (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
Investments in pooled trust preferred securities |  |
Amortized Cost | $ 1,264,529 | $ 674,104
Fair Value | 1,250,777 | 671,488
Gross Unrealized Losses | (18,269) | (10,488)
Trust preferred securities |  |
Investments in pooled trust preferred securities |  |
Amortized Cost | 12,359 | 12,442
Fair Value | 10,633 | $ 9,388
Gross Unrealized Losses | (1,726) |
XXIII |  |
Investments in pooled trust preferred securities |  |
Amortized Cost | 8,292 |
Fair Value | 6,956 |
Gross Unrealized Losses | $ (1,336) |
Issuers currently in deferral or default (percent) | 16.00% |
XXVI |  |
Investments in pooled trust preferred securities |  |
Amortized Cost | $ 4,067 |
Fair Value | 3,677 |
Gross Unrealized Losses | $ (390) |
Issuers currently in deferral or default (percent) | 19.00% |

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